1.9. Trimming Blanks from a String
$zipcode = trim($_REQUEST['zipcode']); $no_linefeed = rtrim($_REQUEST['text']); $name = ltrim($_REQUEST['name']);
Trimming whitespace off of strings saves storage space and can make for more precise display of formatted data or text within <pre> tags, for example. If you are doing comparisons with user input, you should trim the data first, so that someone who mistakenly enters "98052 " as their Zip Code isn't forced to fix an error that really isn't. Trimming before exact text comparisons also ensures that, for example, "salami\n" equals "salami." It's also a good idea to normalize string data by trimming it before storing it in a database.
The trim( ) functions can also remove user-specified characters from strings. Pass the characters you want to remove as a second argument. You can indicate a range of characters with two dots between the first and last characters in the range.
// Remove numerals and space from the beginning of the line print ltrim('10 PRINT A$',' 0..9'); // Remove semicolon from the end of the line print rtrim('SELECT * FROM turtles;',';'); PRINT A$ SELECT * FROM turtles
PHP also provides chop( ) as an alias for rtrim( ). However, you're best off using rtrim( ) instead, because PHP's chop( ) behaves differently than Perl's chop( ) (which is deprecated in favor of chomp( ), anyway) and using it can confuse others when they read your code.
1.9.4. See Also
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